4株鹅源新城疫病毒融合蛋白基因的克隆及序列分析

Sequence Analysis of the Fusion(F) Protein Genes of Four Newcastle DiseaseVirus Strains Causing Clinical Disease in Geese

测定了 4株鹅源新城疫病毒 (NDV)融合蛋白 (F)基因 5’端 1 70 0核苷酸片段的序列 ,并由此推导了F蛋白氨基酸序列 ,并对鹅源NDV的基因型分类地位进行探讨。结果表明 ,4株病毒F基因的同源性大于 97% ,与DNV标准强毒株F48E8F基因的同源性为 86 0 %～86 8% ,F基因转录起始序列及起始密码子位置与已知NDV完全相同 ;F蛋白具有和已知NDV相似的各种功能区 ,F蛋白前体F0裂解位点附近的氨基酸序列为112 RRQKRF117,符合NDV强毒株的特征。对F基因第 3 3 4～ 1 6 82位核苷酸之间 3种限制性内切酶HinfⅠ、BstoⅠ、RsaⅠ酶切图谱的分析表明 。

Four strains of Newcastle disease virus(NDV), which have proven to be responsible for the disease outbreaks in south and east China reigons called !geese paramyxovirus infection' or !avian paramyxovirus infection of geese', were examined for the features of their fusion(F) protein genes. A 1700 nucleotides(nt) fragment of the F gene (1705nt) of each of the 4 strains were sequenced, the results revealed that the NDV strains of goose origin share common transcriptional sequence and translational start position with the hitherto reported NDV, the F gene homologies among the 4 strains were 97^8%～98^9%, while the corresponding homologies between these strains and the standard challenge strain F48E8 were only 86^0～86^8%. The deduced amino acid sequences near cleavage site of F0 proteins showed a 112RRQKR/F 117 motif, comforming well with that of the virulent strains. The cleavage sites distribution of 3 restriction enzymes(HinfⅠ, BstoⅠ,RsaⅠ) in 75% region of the F gene(between 334～1682nt), which is used to group NDV strains into different genotypes, were also analysed with the aid of computer program MegAlign, it is very interesting to find that the 4 strains showed a distinct distribution pattern from all the genotypes so far reported(genotype Ⅰ～Ⅷ), characterized by the simultaneously presence of a BstoⅠ site at 752nt and two RsaⅠ sites at 872nt and 973nt. Additionally, 3 out of the 4 strains, despite their different geographical locations, showed a novel RsaⅠ site at position 1249 which is absent in all of the other genotypes. The 4 NDV strains of goose origin were essentially virulent ones, and probably belong to a new genotype.